Radermachera sinica (China doll, "Sendankisasage")

Japanese name: センダンキササゲ （栴檀木豇豆）
Scientific name: Radermachera sinica

[Overview]
An evergreen tree 10 m tall, but it drops its leaves when temperatures fall.
Under good conditions it can reach 30 m in height and 1 m in diameter.
The leaves are opposite and bipinnately compound with an odd terminal leaflet, 20–70 cm long.
The leaflets are ovate to ovate-lanceolate, 4–7 cm long and 2–3.5 cm wide, hairless and glossy on the upper surface.
The leaf margins are entire or slightly notched.
The leaflets have short leaflet stalks.
A panicle 25–35 cm long emerges at the branch tips.
The flowers are yellowish white to white, 8–12 cm long and about 5 cm across, salverform, with the tip split into 5 lobes in a two-lipped manner.
The tube gradually widens.
The calyx is tubular and 5-lobed.
The fruit is a slender, hanging capsule, and the seeds are winged.

[Cultivation]
Propagate from seed, by cuttings, or by layering.
It tolerates temperatures down to about 2–3°C, so bring it indoors to a sunny spot in winter.
Protect it from cold winter winds and frost.
It prefers sunny, well-drained soil.
Take care not to overwater; for potted plants, water thoroughly from spring to autumn when the soil surface dries, and keep it on the dry side in winter.
For plants in the ground, rainfall is sufficient.
From spring to autumn, apply slow-release chemical fertilizer once a month, placed on the soil.
Pests include aphids and spider mites.

[Notes]
It resembles Radermachera peninsularis, but Radermachera peninsularis has a corolla about 6–7 cm long and bell-shaped.

View this page in Japanese (日本語)